Dispensing means for washing appliance



Jan. 14, 1969 sw M 3,421,660

DISPENSING MEANS FOR WASHING APPLIANCE Filed July 18, 1966 Sheet INVENTOR. NORMAN T. SWETNAM H\s ATTORNEY Jan. 14, 1969 sw M 3,421,660

DISPENSING MEANS FOR WASHING APPLIANCE Filed July 18, 1966 Sheet 2 of 2 FIGJ INVENTOR. .NORMAN T. SWETNAM MW gawk H\s ATTORNEY 3,421,660 DISPENSING MEANS FOR WASHING APPLIANCE Norman T. Swetnam, Louisville, Ky., assignor to General Electric Company, a corporation of New York Filed July 18, 1966, Ser. No. 565,976 US. Cl. 222-76 6- Claims Int. Cl. B67d /06 ABSTRACT OF THE DISCLOSURE Lost-motion means for interconnecting the cocking or trip mechanism of a washing additive dispenser with the operating handle of the latch means for the wash chamber access door of a washing machine, whereby the dispenser cocking mechanism can be cocked through operation of the door latch handle but is free to move to its uncooked position without movement of the door latch means.

This invention relates generallyto washing appliances such as, for example, an automatic dishwasher and, more specifically, to an improved dispensing means to dispense a washing additive into the Wash chamber of a washing appliance.

Additive dispensing means for automatic washing machines are well known and extensively used commercially. In an automatic dishwasher, for'example, means are provided to automatically dispense detergent and rinse aid. The purpose of the detergent will be obvious to anyone who has washed dishes, by hand or machine. The purpose of rinse aid is to prevent, or at least minimize, water spots on dishes which materialize during the drying cycle of the dishwasher due to mineral deposits remaining after evaporation of the water. The rinse aid is a wetting agent, generally dispensed into the Wash chamber of the machine during the final rinse, which encourages the water to sheet off the dishes or other articles rather than form small spherical drops. As is common with wetting agents, this is accomplished by reducing the surface tension of the water. With either a detergent dispenser or a rinse aid dispenser, it is desirableto have the dispenser operate automatically at a predetermined point during the operational cycle of the machine. If it were necessary for the operator to trigger the dispenser manually, the automatic characteristics of the Washing machine would be significantly compromised since it would be necessary for the operator to stand by until the appropriate time arrived to operate the dispenser.-In order to achieve automatic operation conveniently and economically, it is necessary to provide energy storing means, such as a spring-loaded mechanism, so that the sequence control means can trigger the dispenser-and dispense the desired amount of additivewithout exerting substantial power. The spring-loaded mechanism heretofore has required special act by the operator to cock it. That is, the operator would normally have to manipulate a cocking handle projecting from the dishwasher cabinet in order to load the spring and effective cocking of the dispensing mechanism. Because this separate act by the operator was required, additive was frequently not dispensed simply because the operator forgot to cock the mechanism. Accordingly, it would be desirable to provide means to automatically cock or energize the additive dispensing means in an automatic washing machine.

As noted above, the present invention contemplates automatic energization of the additive dispensing means which will result in automatic dispensing of additive during each cycle of the washing machine. Inasmuch as there may be reasons for omitting the additive during some operations of the washing machine it would be advantageous to provide means for selective operation of the United States Patent 0 3,421,660 Patented Jan. 14, 1969 ice dispenser even though energization of the dispenser automatically occurs during each dishwasher cycle.

It is an object of this invention to provide an improved dispensing means for dispensing a washing additive into the wash chamber of an automatic washing machine.

It is another object of this invention to provide improved means to automatically energize a washing additive dispenser associated with a washing appliance.

It is a further object of this invention to provide means which automatically energizes a dispensing means associated with a washing appliance each time the washing appliance is operated but which also allows selective utilization of the dispensing means.

Other objects will become obvious as the description proceeds.

Briefly stated, in accordance with one aspect of the present invention, there is provided an automatic washing machine having a wash chamber and an access opening into the wash chamber. A closure member for the access opening is provided and is movable between open and closed positions. Dispensing means to dispense a washing additive into the wash chamber are provided and include a spring-biased cocking mechanism having at least a cocked position and an uncooked position. A latch mechanism is provided to latch the closure member in the closed position. The latch mechanism includes a manuallyoperable handle adapted to be moved between at least two positions, one of the posit-ions corresponding to a latched position for the latch mechanism and the other position corresponding to an unlatched position for the latch mechanism. Also, means are provided to interconnect the latch mechanism and the cocking mechanism and include a lost motion arrangement 'whereby movement of the handle between the two positions will move the cocking mechanism to the cocked position from the uncocked position but the cocking mechanism is free to move from the cocked position to the uncooked position without movement of the latch mechanism.

While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention, it is believed the invention will be better understood from the following description taken in connection with the accompanying drawings, in which:

FIGURE 1 is a fragmentary elevational view, partially cut away to show details, of an automatic washing appliance employing the present invention;

FIGURE 2 is a fragmentary sectional view taken along line 22 of FIGURE 1;

FIGURE 3 is a view similar to FIGURE 2 but showing the apparatus in a difierent operational condition; and

FIGURE 4 is a schematic circuit diagram of a control system for the washing appliance of FIGURE 1.

Referring now to the drawings, and particularly to FIG- URE 1 thereof, there is illustrated an automatic washing appliance in the form of an automatic dishwasher 10 having an outer cabinet 11 which defines therein a wash chamber 12. Disposed within wash chamber 12 are dishsupporting racks 13 and 14 which are adapted to receive and support articles to be washed within wash chamber 12. Access to wash chamber 12 is provided by an opening in one wall of cabinet 11 and a closure member or door 15 is provided to seal this opening during operation of dishwasher 10. Door 15 is pivotal about a hinge 16, it being understood that a second hinge identical to hinge 16 is provided at the opposite side of door 15 but is not visible in FIGURE 1 since it lies directly behind hinge 16 shown. A counterbalance arm 17 is secured to door 15 by means of a bracket 18 and moves with door 15. A spring 19 has one end secured to arm 17 and the other end secured to cabinet 11 at a point not shown. As door 15 is pivoted downwardly to provide access to wash chamher 12, spring 19 is stretched to provide a counterbalance force to facilitate closing of the door 15.

Racks 13 and 14 are at least partially withdrawable from wash chamber 12 when door 15 is in its open position, it being understood that the open position of door 15 puts door 15 in a substantially horizontal attitude. Rack 14 is provided with a plurality of rollers (not shown) which travel along at rack 20 and, as rack 14 is withdrawn from wash chamber 12, the rollers travel onto the upwardly facing surface of the door 15. Rack 13 is made withdrawable from wash chamber 12 by means of a slide assembly 21 which includes a plurality of rollers 22 which are carried by cabinet 11 and are free to rotate about their respective central axes. A slide 23 is carried by rollers 22 and is free to move relative thereto. Rack 13 has a plurality of rollers 24, which are received in elongated slots 25 in slide 23, only one of rollers 24 being visible in FIGURE 1. With the foregoing arrangement, the operator of dishwasher may grasp rack 13 and pull it out through the access opening with roller 24 moving relative to slide 23 and slide 23 moving relative to rollers 22.

The lower extremity of wash chamber 12 is defined by a bottom wall 26 having a centrally depressed portion forming a sump 27. Disposed within sump 27 and supported by bottom wall 26 is a motor-pump assembly 28 which includes an electrically-reversible motor 29 and a pump 30. Pump 30 is of the reversible type wherein, in one direction of rotation, fluid will be withdrawn from sump 27 through an inlet 31 and propelled upwardly into a reaction type spray arm 32 from which it will be sprayed into wash chamber 12 to effectuate a wash action upon articles supported by racks 13 and 14. It is to be understood that pump 30 and motor 29 are mechanically interconnected so that whenever motor 29 rotates, pump 30 rotates in the same direction. The reaction type spray arm 32 has a plurality of orifices some of which are angled in a manner whereby spray arm 32 will be rotated due to the reaction force created as the fluid issues from those angle orifices. Spray arm 32 is carried by the housing of pump 30 in a manner whereby it is free to rotate relative to that housing. In the opposite direction of rotation of motor 29 and pump 30, fluid withdrawn from sump 27 through inlet 31 and propelled out through an eflluent discharge outlet 33 which communicates with the normal household sewer system (not shown).

The aforedescribed arrangement comprises a substantially conventional present day automatic dishwasher. Such a dishwasher has a conventional operational cycle which includes an initial admission of water to wash chamber 12 in a predetermined quantity. This water collects in sump 27. Once the water has been admitted, motor 29 is energized and pump 30 rotates in a direction wherein the water is withdrawn from sump 27 through inlet 31 and propelled upwardly through spray arm 32. This condition prevails for a few minutes after which time motor 29 is de-energized and then re-energized in the opposite direction so that the water will be discharged through outlet 33. The foregoing series of operations constitutes a pro-rinse. The pre-rinse may be followed by a second pre-rinse comprising identical series of operations and this in turn may be followed by a wash cycle which constitutes an elongated rinse cycle with the addition of detergent to the water in wash chamber 12. After the wash cycle, there follows'one or more post-rinses, each of which comprises precisely the same series of operations as the pre-rinses. During the early portion of the final post-rinse, o. rinse aid maybe injected into wash chamber 12 to go into solution in the water contained therein for the purposes described earlier in this specification. Following the final post-rinse is a drying cycle during which an electrical resistance heating element 34 may be energized to facilitate drying of the articles supported by racks 13 and 14.

As mentioned above, door provides access to wash chamber 12 so that articles may be placed into, or removed from, racks 13 and 14. Because spray arm 32 etfectuates a vigorous spray action within wash chamber- 12, it is necessary that door 15 remain closed during operation of the dishwasher and maintain a water tight seal relative to the cabinet about the access opening. A gasket 35 is provided to maintain a water tight seal between door 15 and cabinet 11. Also, a latch mechanism 36 is provided to secure door 15 in the closed position as shown in FIGURE 1. Latch mechanism 36 includes a manually-operable handle 37 which projects beyond the outer wall of door 15 and is adapted to be moved between a latched position (FIGURES l and 2) and an unlatched position (FIGURE 3). Latch mechanism 36 further includes a hook-like element 38 which moves with handle 37 to engage cabinet 11 and secure door 15 in its closed position when handle 37 is moved to the latched position. A spring 3811 extends between handle 37 and a stationary portion of latch mechanism 36 to make the latch mechanism bi-stable, i.e., it will remain in either the latched or unlatched position until manually moved therefrom. Door 15 comprises an inner wall 39 and an outer wall 40 spaced from each other to form a chamber 41 within which the major portion of latch mechanism 36 is disposed with only handle 37 projecting out through wall 40 and element 38 projecting out through wall 39.

'Also disposed within chamber 41 is a dispensing means 42. Dispensing means 42 includes a reservoir portion 43 capable of containing a supply of washing additives such as, for example, rinse aid suificient to .serve for several cycles of operation of the dishwasher 10. A dispensing mechanism is also disposed within reservoir portion 43 and is adapted to pump or dispense a predetermined quantity or rinse aid into wash chamber 12 upon release of a cocking or trip mechanism 44. Trip mechanism 44 is biased toward the dispensing position by a spring 45. Referring to FIGURE 2, dispensing means 42 dispenses a predetermined quantity of additive to wash chamber 12 as trip mechanism 44 moves from the solid line position to the dotted line position, it being understood that additional mechanism within reservoir portion 43 (not shown) is mechanically linked to the cocking or trip mechanism 44 to carry out the dispensing function as the aforedescribed movement of the trip mechanism 44 takes place. A cap 46 is disposed beyond wall 39 to cover an inlet through which additive is admitted to replenish the liquid contained within reservoir portion 43. Except for the cocking or trip mechanism 44, which is to be discussed in greater detail hereinafter, dispensing means 42 may be substantially as described and claimed in US. Patent No. 3,198,387, issued to Norman L. Kendt and John A. Dicken, In, on Aug. 3, 1965, and assigned to the General Electric Company, assignee of the present invention. For the purposes of the present invention, it is only necessary to note that dispensing means 42 dispenses a predetermined charge of rinse aid into wash chamber 12 as trip mechanism 44 is rotated by spring 45.

In accordance with the present invention, means are provided to automatically cook or energize the additive dispensing means 42. The means include a link 47 which is secured at one end to latch mechanism 36 by means of a pin 48 so that as handle 37 is moved between the latched position of FIGURE 2 and the unlatched position of FIGURE 3, link 47 moves therewith. The other end of link 47 is provided with an elongated slot 49 which receives a pin 50. Pin 50 is rigidly secured to trip mechanism 44 and loosely fits within slot 49 so that it is free to move, relative to link 47, an extent equal to the length of elongated slot 49.

Trip mechanism 44 is pivotal about a pin 51 carried by the body of dispensing means 42. A small projection 52 is adapted to engage a stop 53 whereby movement of trip mechanism 44, in the clockwise direction as viewed in FIGURES 2 and 3, is limited by engagement between projection 52 and stop 53. The distal end of trip mechanism 44 includes a catch 54 which engages a U-shaped current-responsive bimetal element 55 when trip mechanism 44 is rotated in the counterclockwise direction. Catch 54 has a beveled surface 56 which cams element 55 out of the way so that catch 54 may pass down into the element 55 and be retained in the position shown in solid lines in FIGURE 2 by the bifurcation of the bimetal element 55.

With the foregoing arrangement, each time handle 37 is moved from the latched position of FIGURE 2 to the unlatched position of FIGURE 3, which must occur each time door 15 is opened, link 47 is moved from the position shown in FIGURE 2 to the position shown in FIG- URE 3. If trip mechanism 44 has been released, or tripped, prior to the movement of handle 37, link 47 will engage pin 50 and rotate trip mechanism 44 to the cocked position of FIGURE 3 as handle 37 is moved to the unlatched position. During subsequent movements of handle 37 between the latched and unlatched positions, trip mechanism 44 will remain cocked due to engagement between element 55 and catch 54, and link 47 will simply move relative to pin 50 due to the elongation of slot 49. In other words, the present invention provides a lost motion relationship between latch mechanism 36 and trip mechanism 44. When handle 37 and the other components of latch mechanism 36 are in the latched position of FIGURE 2, trip mechanism 44 is free to move from the cocked position to the uncocked position since pin 50 is free to slide the length of elongated slot 49.

Thus it can be seen that the present invention provides means to automatically cock or energize an additive dispensing means in an automatic washing machine without requiring a special act by the operator since the cocking is effected by unlatching the door.

Referring now to FIGURE 4, a schematic electrical circuit diagram of an appropriate control system for dishwasher is shown. Power is provided to the control system across lines L and L which, in an ordinary household installation, would be 115 volts AC at 60 cycles. A synchronous electric motor 57 is mechanically linked to a plurality of earns 58, 59, 60, 61, 62 and 63 which operate switches 64, 65, 66, 67, 68 and 69 respectively. A main switch 70 is preferably provided and is mechanically associated with latch mechanism 36 such that the control system cannot be energized until latch mechanism 36 is in a position wherein door is secured in water tight relationship with cabinet 11. Switch 70 thus prevents inadvertent energization of motor 29 when door 15 is opened which would result in water issuing from spray arm 32 escaping from wash chamber 12.

Switch 64 controls energization of motor 57. Motor 57 is preferably mounted within chamber 41 and is provided with a manually rotatable knob which projects out beyond wall 40. The knob and motor 57 are not shown in FIG- URE l inasmuch as they would be located in that portion of door 15 which is cut away to show the details of latch mechanism 36 and dispensing means 42. Operation of dishwasher 10 is initiated by manually rotating the knob a few degrees which causes cam 58 to close switch 64, thereby energizing motor 57. From this point on, motor 57 will rotate cams 58-63 through an entire operational cycle following the termination of which, cam 58 will allow switch 64 to open thereby de-energizing motor 57.

Switch 65 controls bimetal element 55. Bimetal element 55 may be of the conventional laminated construction and, when current passes therethrough, it flexes to the position shown in dotted lines in FIGURE 2 thus passing out beyond catch 54 thereby releasing trip mechanism 44 to pivot under the infiunece of spring 45. A manually operable selector switch 71 may be provided to allow the operator of the dishwasher to selectively omit dispensing of additive into wash chamber 12 by dispensing means 42. If switch 7 1 is opened by the operator, current will not flow through element 55 when cam 59 closes switch 65 due to the series relationship between switch 71 and element 55. If the operator has closed switch 71, then element 55 will be energized by switch 65 during the appropriate point in the operational cycle of the dishwasher to dispense the additive into wash chamber 12. -It is to be understood that switch 71 is a bi-stable switch which will remain in either the open or closed position until operated manually.

Switch 66 controls the energization of a water valve 72 which admits water to wash chamber 12 from the normal household plumbing system. Switch 67 controls the energization of electrical resistance heating element 34. Switches 68 and 69 control the operation of motor 29. Motor 29 includes a run winding 73 and a pair of start windings 74 and 75. Switch 68 controls the energization of both the run winding and one of the start windings and switch 69 determines which of the start windings is energized upon closing of switch 68. A current responsive relay 76 de-energizes the start winding once motor 29 has approached normal running speed. With the exception of bimetal element 55 and its asociated switches 71 and 65, the control system schematically represented by FIGURE 4 is substantially conventional, being otherwise generally similar to the control system described in detail in US. Patent No. 3,286,149 issued to Donald S. Cushing on Nov. 15, 1966, and assigned to the General Electric Company, assignee of the present invention.

Cam 59 is configurated to close switch 65 at the appropriate time, i.e., during the final post-rinse as described above, to allow current to pass through element 55. This current will cause element 55 to flex to the dotted position shown in FIGURE 2 which will release trip mechanism 44 and effect a dispensing of additive into wash chamber 12, provided switch 71 has been previously closed by the operator.

Thus it can be seen that the present invention provides means for selective operation of the dispenser even though energization or cocking of the dispenser automatically occurs during each dishwasher cycle.

As will be evident from the foregoing description, certain aspects of the invention are not limited to the particular details of construction of the example illustrated, and it is contemplated that various other modifications or applications will occur to those skilled in the art. It is therefore intended that the appended claims shall cover such modifications and applications as do not depart from the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In an automatic washing machine having a wash chamber and an access opening into said wash chamber, a closure member for said access opening movable between open and closed positions, and dispensing means to dispense a washing additive into said wash chamber, said dispensing means including a spring-biased cocking mechanism having at least a cocked position and an uncocked position, the invention comprising:

(a) a latch mechanism to latch said closure member in the closed position,

(b) said latch mechanism including a manuallyoperable handle adapted to be moved between at least two positions, one of said positions corresponding to a latched position for said latch mechanism and the other of said positions corresponding to an unlatched position for said latch mechanism, and

(0) means interconnecting said latch mechanism and said cocking mechanismand including a lost motion arrangement whereby movement of said handle between said two positions will move said cocking mechanism to said cocked position from said uncocked position but said cocking mechanism is free to move from said cocked position to said uncocked position without'movement of said latch mechanism.

2. The invention of claim 1 wherein said means interconnecting said latch mechanism and said cocking mechanism comprises a link having a connection adjacent one end to said latch mechanism and a conection adjacent its other end to said cocking mechanism, one of said connections comprising an elongated slot within which is received a pin whereby said link may move relative to said pin in at least one direction to thereby provide said lost motion arrangement.

3. The invention of claim 1 further comprising an element adapted to engage said cocking mechanism when said cocking mechanism is moved to said cocked position and restrain said cocking mechanism from movement toward said uncooked position.

4. The invention of claim 3 wherein said element is a current-responsive bimetal element and is adapted to disengage from said cocking mechanism when subjected to current passing therethrough.

5. The invention of claim 4 further comprising a manually-operable selector switch in electrical series cir cuit with said element and a cam-operated switch also in electrical series circuit with said element whereby said cam-operated switch will allow current to flow through said element only when said selected switch is closed.

6. In an automatic washing machine having a wash chamber access opening closure member pivotal between open and closed positions, and a dispensing means having a spring-biased trip mechanism, the invention comprising:

(a) a latch mechanism to latch the closure member in the closed position,

(b) said latch mechanism including a manuallyoperable handle projecting from the closure member and adapted to be moved between a latched position and an unlatched position,

(c) a link interconnecting said latch mechanism and said spring-biased trip mechanism,

(d) at least one end of said link being connected to one of said mechanisms with a lost motion relationship whereby initial movement of said manuallyoperable handle between said latched position and said unlatched position will cause movement of said spring-biased trip mechanism but subsequent movement of said manually-operable handle will result in lost motion between said link and said one of said mechanisms.

References Cited UNITED STATES PATENTS 2,211,107 8/1940 Fisher et a1. 200-116 2,468,584 4/1949 Wotring 292-216 2,478,814 8/ 1949 Ferris 134-57 2,683,050 7/1954 Allen 292-216 3,012,696 12/1961 Kendt 222-166 3,212,675 10/1965 Krzewina 222-166 X ROBERT B. REEVES, Primary Examiner.

NORMAN L. STACK, Assistant Examiner.

US. Cl. X.R. 134-58; 200-116 

